A little over 2200 years ago, the Roman navy attacked the Greek port city of Syracuse. According to some ancient historians, the Greeks defended themselves with an ingenious weapon called a “burning mirror”: a polished copper surface curved to focus the Sun’s rays onto Roman ships, causing them to catch fire. However, we have several reasons to suspect that the story of the burning mirror is just a myth and the Greeks of Syracuse never really built such a device.
First, the ancient Greeks were not technologically advanced enough to make such a device. A mirror that would focus sunlight with sufficient intensity to set ships on fire would have to be several meters wide. Moreover, the mirror would have to have a very precise parabolic curvature (a curvature derived from a geometric shape known as the parabola). The technology for manufacturing a large sheet of copper with such specifications did not exist in the ancient world.
Second, the burning mirror would have taken a long time to set the ships on fire. In an experiment conducted to determine whether a burning mirror was feasible, a device concentrating the Sun’s rays on a wooden object 30 meters away took ten minutes to set the object on fire; and during that time, the object had to be unmoving. It is unlikely that Roman ships stayed perfectly still for that much time. Such a weapon would therefore have been very impractical and ineffective.
Third, a burning mirror does not seem like an improvement on a weapon that the Greeks already had: flaming arrow. Shooting at an enemy’s ships with flaming arrows was a common way of setting the ships on fire. The burning mirror and flaming arrows would have been effective at about the same distance. So the Greek had no reason to build a weapon like a burning mirror
The reading and the lecture are both about whether greeks used a burning mirror, which is believed that they built for setting roman ships on fire. The author of the reading believes there are three reasons it is a myth. The lecturer challenges that statements made by the author. she says none of the author's explanations are convincing.
First of all, the author suggests that the technology of Greeks at that time were not that advanced. it is mentioned that a mirror for causing fire on ships must be really big and parabolic in shape. but such thing was not possible at that time. The argument is refuted by the lecturer. she says Greeks may have used not single sheet of mirror, but several of them. Furthermore, she argues that it is possible for many sheets to arrange them into a parabolic shape.
Secondly, the article posits that such a mirror would needed significant amount of times to set ships on fire. The author notes as seen from an experiment that a device like that from 30 meters away from a target needed 10 minutes to start fire on a wood and also be motionless. The lecturer, however, casts doubt on this by asserting that the author made assumption of a wood, but roman ships were not fully wooden. she elaborates on this by mentioning that the ships' materials were glued together by a sticky substance, which is easily flammable. As a result, the sticky substances would likely cause the fire even if the ship was moving.
Finally, it is stated in the reading that Greeks had already other superior weapons. The author establishes that flaming arrow is as much, if not more, effective as the burning mirror. The lecturer, on the other hand, opposes that romans were familiar with flaming arrows. As a result they would be much prepared, but not for the burning mirror. she puts forth the idea that the mirror must be more surprising that romans ships caught on fire by some kind of magic.
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| 2020-01-17 | Shiimaaa | 80 | view |
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Grammar and spelling errors:
Line 1, column 222, Rule ID: ENGLISH_WORD_REPEAT_BEGINNING_RULE
Message: Three successive sentences begin with the same word. Reword the sentence or use a thesaurus to find a synonym.
...s there are three reasons it is a myth. The lecturer challenges that statements mad...
^^^
Line 1, column 282, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: She
...ges that statements made by the author. she says none of the authors explanations a...
^^^
Line 3, column 102, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: It
...ks at that time were not that advanced. it is mentioned that a mirror for causing ...
^^
Line 3, column 181, Rule ID: ADJECTIVE_IN_ATTRIBUTE[1]
Message: A more concise phrase may lose no meaning and sound more powerful.
Suggestion: parabolic
...ng fire on ships must be really big and parabolic in shape. but such thing was not possible at tha...
^^^^^^^^^^^^^^^^^^
Line 3, column 201, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: But
...t be really big and parabolic in shape. but such thing was not possible at that tim...
^^^
Line 3, column 288, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: She
...he argument is refuted by the lecturer. she says Greeks may have used not single sh...
^^^
Line 5, column 55, Rule ID: DID_BASEFORM[1]
Message: The verb 'would' requires the base form of the verb: 'need'
Suggestion: need
...article posits that such a mirror would needed significant amount of times to set ship...
^^^^^^
Line 5, column 418, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: She
... but roman ships were not fully wooden. she elaborates on this by mentioning that t...
^^^
Line 7, column 347, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: She
...epared, but not for the burning mirror. she puts forth the idea that the mirror mus...
^^^
Transition Words or Phrases used:
also, but, finally, first, furthermore, however, if, may, really, second, secondly, so, kind of, as a result, first of all, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 21.0 10.4613686534 201% => Less to be verbs wanted.
Auxiliary verbs: 6.0 5.04856512141 119% => OK
Conjunction : 7.0 7.30242825607 96% => OK
Relative clauses : 20.0 12.0772626932 166% => OK
Pronoun: 33.0 22.412803532 147% => Less pronouns wanted
Preposition: 38.0 30.3222958057 125% => OK
Nominalization: 4.0 5.01324503311 80% => OK
Performance on vocabulary words:
No of characters: 1582.0 1373.03311258 115% => OK
No of words: 339.0 270.72406181 125% => OK
Chars per words: 4.66666666667 5.08290768461 92% => OK
Fourth root words length: 4.29091512845 4.04702891845 106% => OK
Word Length SD: 2.38610431276 2.5805825403 92% => OK
Unique words: 174.0 145.348785872 120% => OK
Unique words percentage: 0.513274336283 0.540411800872 95% => More unique words wanted or less content wanted.
syllable_count: 487.8 419.366225166 116% => OK
avg_syllables_per_word: 1.4 1.55342163355 90% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 7.0 3.25607064018 215% => Less pronouns wanted as sentence beginning.
Article: 11.0 8.23620309051 134% => OK
Subordination: 3.0 1.25165562914 240% => Less adverbial clause wanted.
Conjunction: 4.0 1.51434878587 264% => Less conjunction wanted as sentence beginning.
Preposition: 1.0 2.5761589404 39% => More preposition wanted as sentence beginning.
Performance on sentences:
How many sentences: 20.0 13.0662251656 153% => OK
Sentence length: 16.0 21.2450331126 75% => The Avg. Sentence Length is relatively short.
Sentence length SD: 32.8822140374 49.2860985944 67% => OK
Chars per sentence: 79.1 110.228320801 72% => OK
Words per sentence: 16.95 21.698381199 78% => OK
Discourse Markers: 7.05 7.06452816374 100% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 9.0 4.19205298013 215% => Less language errors wanted.
Sentences with positive sentiment : 7.0 4.33554083885 161% => OK
Sentences with negative sentiment : 10.0 4.45695364238 224% => Less negative sentences wanted.
Sentences with neutral sentiment: 3.0 4.27373068433 70% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.0997504423139 0.272083759551 37% => The similarity between the topic and the content is low.
Sentence topic coherence: 0.0316686677266 0.0996497079465 32% => Sentence topic similarity is low.
Sentence topic coherence SD: 0.0329321836833 0.0662205650399 50% => Sentences are similar to each other.
Paragraph topic coherence: 0.0681700444548 0.162205337803 42% => OK
Paragraph topic coherence SD: 0.0354201772871 0.0443174109184 80% => OK
Essay readability:
automated_readability_index: 9.0 13.3589403974 67% => Automated_readability_index is low.
flesch_reading_ease: 72.16 53.8541721854 134% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 7.2 11.0289183223 65% => OK
coleman_liau_index: 9.51 12.2367328918 78% => OK
dale_chall_readability_score: 7.64 8.42419426049 91% => OK
difficult_words: 69.0 63.6247240618 108% => OK
linsear_write_formula: 6.5 10.7273730684 61% => OK
gunning_fog: 8.4 10.498013245 80% => OK
text_standard: 8.0 11.2008830022 71% => OK
What are above readability scores?
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Write the essay in 20 minutes.
It is not exactly right on the topic in the view of e-grader. Maybe there is a wrong essay topic.
Rates: 3.33333333333 out of 100
Scores by essay e-grader: 1.0 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.